<!DOCTYPE html>

<html>

<head>
	<title>Rigid body - Physijs</title>
	
	<link rel="stylesheet" type="text/css" href="css/styles.css" />
	
	<script type="text/javascript" src="js/three.min.js"></script>
	<script type="text/javascript" src="js/stats.js"></script>
	<script type="text/javascript" src="../physi.js"></script>
	
	<script type="text/javascript">
	
	'use strict';
	
	Physijs.scripts.worker = '../physijs_worker.js';
	Physijs.scripts.ammo = 'examples/js/ammo.js';
	
	var initScene, render, applyForce, setMousePosition, mouse_position,
		ground_material, box_material, loader,
		renderer, render_stats, physics_stats, scene, ground, light, camera, box, boxes = [];
	
	initScene = function() {
		renderer = new THREE.WebGLRenderer({ antialias: true });
		renderer.setSize( window.innerWidth, window.innerHeight );
		renderer.shadowMap.enabled = true;
		renderer.shadowMapSoft = true;
		document.getElementById( 'viewport' ).appendChild( renderer.domElement );
		
		render_stats = new Stats();
		render_stats.domElement.style.position = 'absolute';
		render_stats.domElement.style.top = '1px';
		render_stats.domElement.style.zIndex = 100;
		document.getElementById( 'viewport' ).appendChild( render_stats.domElement );

		physics_stats = new Stats();
		physics_stats.domElement.style.position = 'absolute';
		physics_stats.domElement.style.top = '50px';
		physics_stats.domElement.style.zIndex = 100;
		document.getElementById( 'viewport' ).appendChild( physics_stats.domElement );
		
		scene = new Physijs.Scene;
		scene.setGravity(new THREE.Vector3( 0, -30, 0 ));
		scene.addEventListener(
			'update',
			function() {
				applyForce();
				scene.simulate( undefined, 1 );
				physics_stats.update();
			}
		);
		
		camera = new THREE.PerspectiveCamera(
			35,
			window.innerWidth / window.innerHeight,
			1,
			1000
		);
		camera.position.set( 60, 50, 60 );
		camera.lookAt( scene.position );
		scene.add( camera );
		
		// Light
		light = new THREE.DirectionalLight( 0xFFFFFF );
		light.position.set( 20, 40, -15 );
		light.target.position.copy( scene.position );
		light.castShadow = true;
		light.shadowCameraLeft = -60;
		light.shadowCameraTop = -60;
		light.shadowCameraRight = 60;
		light.shadowCameraBottom = 60;
		light.shadowCameraNear = 20;
		light.shadowCameraFar = 200;
		light.shadowBias = -.0001
		light.shadowMapWidth = light.shadowMapHeight = 2048;
		light.shadowDarkness = .7;
		scene.add( light );

		// Loader
		loader = new THREE.TextureLoader();
		
		// Materials
		ground_material = Physijs.createMaterial(
			new THREE.MeshLambertMaterial({ map: loader.load( 'images/rocks.jpg' ) }),
			.8, // high friction
			.4 // low restitution
		);
		ground_material.map.wrapS = ground_material.map.wrapT = THREE.RepeatWrapping;
		ground_material.map.repeat.set( 3, 3 );
		
		box_material = Physijs.createMaterial(
			new THREE.MeshLambertMaterial({ map: loader.load( 'images/plywood.jpg' ) }),
			.4, // low friction
			.6 // high restitution
		);
		box_material.map.wrapS = ground_material.map.wrapT = THREE.RepeatWrapping;
		box_material.map.repeat.set( .25, .25 );
		
		// Ground
		ground = new Physijs.BoxMesh(
			new THREE.BoxGeometry(100, 1, 100),
			ground_material,
			0 // mass
		);
		ground.receiveShadow = true;
		scene.add( ground );
		
		for ( var i = 0; i < 10; i++ ) {
			box = new Physijs.BoxMesh(
				new THREE.BoxGeometry( 4, 4, 4 ),
				box_material
			);
			box.position.set(
				Math.random() * 50 - 25,
				10 + Math.random() * 5,
				Math.random() * 50 - 25
			);
			box.rotation.set(
				Math.random() * Math.PI * 2,
				Math.random() * Math.PI * 2,
				Math.random() * Math.PI * 2
			);
			box.scale.set(
				Math.random() * 1 + .5,
				Math.random() * 1 + .5,
				Math.random() * 1 + .5
			);
			box.castShadow = true;
			scene.add( box );
			boxes.push( box );
		}
		
		renderer.domElement.addEventListener( 'mousemove', setMousePosition );

		requestAnimationFrame( render );
		scene.simulate();
	};
	
	render = function() {
		requestAnimationFrame( render );
		renderer.render( scene, camera );
		render_stats.update();
	};
	
	setMousePosition = function( evt ) {
		// Find where mouse cursor intersects the ground plane
		var vector = new THREE.Vector3(
			( evt.clientX / renderer.domElement.clientWidth ) * 2 - 1,
			-( ( evt.clientY / renderer.domElement.clientHeight ) * 2 - 1 ),
			.5
		);
		vector.unproject( camera );
		vector.sub( camera.position ).normalize();
		
		var coefficient = (box.position.y - camera.position.y) / vector.y
		mouse_position = camera.position.clone().add( vector.multiplyScalar( coefficient ) );
	};
	
	applyForce = function() {
		if (!mouse_position) return;
		var strength = 35, distance, effect, offset, box;
		
		for ( var i = 0; i < boxes.length; i++ ) {
			box = boxes[i];
			distance = mouse_position.distanceTo( box.position ),
			effect = mouse_position.clone().sub( box.position ).normalize().multiplyScalar( strength / distance ).negate(),
			offset = mouse_position.clone().sub( box.position );
			box.applyImpulse( effect, offset );
		}
	};
	
	window.onload = initScene;
	
	</script>
</head>

<body>
	<div id="heading">
		<h1>Rigid Body + User Interaction</h1>
		<p>Move your cursor near the boxes to push them.</p>
	</div>
	<div id="viewport"></div>
</body>

</html>
